The current CST rules say that tires must have a treadwear rating of 140 or higher. I don't think that any of the tire manufactures even make a 140 tire anymore. In the spirt of CST, which is to allow any car that can be truly driven on the street to and from an event, I would like to see the treadwear rating changed to 100. This would allow people that are doing track days with the Toyo R888 and R888R to run in CST instead of CSM. These tires have a real tread pattern, unlike the Hoosier and BFG DOT race tires which are basically slicks. They are inexpensive and wear well and don't seem to heat cycle out. The R888R is available in sizes from 13" all the way up to 20". A set of 255/40X17's would cost $205 at The Tire Rack. I'm going to ask that at the next Committee meeting that this be brought before the Voting Committee for a vote. Anybody have any thoughts, positive or negative?

CALIFORNIA STREET TOURING (CST):Vehicles eligible for CST must comply with the rules of CSM, with the exception that all of thetires mounted on the car must have a TREADWEAR number of 140 or higher molded by themanufacturer on the sidewall.

In the title it mentions Street Touring, I believe we should have a 200 treadware limit to match what is currently in the rules for street touring as well as a minimum molded depth of 7/32" as specified by the manufacturer.

If it were 100, there is only 1 tire that would fit my car, the Maxxis RC1 which is 100 treadwear and looks like this.

RC1-2.png (272.29 KiB) Viewed 1691 times

There are a very limited set of 100 treadwear tires for 15" wheels, in addition to everyone wanting to compete in that class having to go down to 100 treadwear tires to be competitive. When looking at the different tire brands and products there are far less choices and options in the 100 treadwear styles.

The Maxxis RC1 is hardly a threat IMO. I have driven fresh ones and they aren't anywhere close to sticky at 120º compared to when they are 180º on track. A BFG or RE71R will be grippier even when comparing 245 vs 205.

I agree with Bob that CST should be more open as those type of participants do gravitate towards CST. Most of the people I know in CST have a lax'd attitude towards autocross (terms of prep) and often do track as well.

I don't really see a reason to really limit CST to 200tw, as the class is supposed to be a "Run What You Brung" class.

I can agree that the 140tw is a bit outdated nowadays.

Honestly, I am not sure if there is any downside to NOT lowering the treadwear restrictions to 100tw.At this point in time, none of the semi-slick tires have proven to be faster at autocross than the BFG Rival S 1.5 nor the Bridgestone RE-71R.So it would be likely to think that the more serious CST competitors would still compete on the top level 200tw tires to get the best overall raw time.

Lowering the treadwear restrictions may invite more "track" oriented drivers to come play, as they would now have a place to compete in a class with their car "as-is",as well as possibly accommodate better for for vehicles at that use 19" and 20" tires. Selection for BFG and Bridgestone is very limited for those larger sizes.

I see no reason to not allow this, it's a run what you brung class. If they can drive the car "legally" on the streets then why restrict them to a specific treadware. Like Jon mentioned, the current crop of "street legal slicks" don't work nearly as well at autox temperatures as the current crop of 200 tw tires do. This should be an easy update to the rulebook for next year and I'm sure we can let people run in class for the remainder of the current season (maybe we just ask the CST field if they are ok with the updated rule change).

Marshall Grice wrote:Why wouldn’t we just kill csm while we are at it? And why limit the treadwear to 100, why not cut straight to the chase and make the treadwear limit something like 41 (hoosiers are treadwear 40)?

Is there a faster autocross tire you know of from 41tw to 200tw than the RE-71R/Rival S?If not, then why not?

I would second Bob's request to update the tire rating to 100. In my case Toyo RA1's.

Being able to run the tires that I will be using on my refreshed NASA spec BMW lets me have seat time at an autocross on the combination that I will be driving on the track. This combination will not be as fast as the car on RE71's, but the RA's last longer on the track.

Making the change is removing the need for yet again another set of tires and rims to entice a potential group of drivers. Again, Track time is not like our events. But seat time is what some of us really need before we go all out on a track, doing "track days".

David Barrish wrote:I would second Bob's request to update the tire rating to 100. In my case Toyo RA1's.

Being able to run the tires that I will be using on my refreshed NASA spec BMW lets me have seat time at an autocross on the combination that I will be driving on the track. This combination will not be as fast as the car on RE71's, but the RA's last longer on the track.

Making the change is removing the need for yet again another set of tires and rims to entice a potential group of drivers. Again, Track time is not like our events. But seat time is what some of us really need before we go all out on a track, doing "track days".

Yeah I like this sentiment. It allows people to bring out their more track oriented cars without having to feel alienated by the Solo rulebook. CST is just for local fun; having big tire style discrepancies shouldn't ruffle too many feathers when you have all manners/levels of prepped cars competing against each other already (RX-7 vs Mini vs S2000 vs etc.).

So I figured I'd chime in here as I'm the only one in the comments that actually competes (regularly) in CST. I was always under the impression that CST followed the treadwear rules of street tire classes and when street tire classes changed from 140tw to 200tw CST followed suite. Of course tire manufacturers also paid attention to this rule change and now all the fast tires are magically 200tw as well. I and my fellow competitors changed with the rules with little to no drama. So here's my only concern, are we modifying the tire rules to accommodate the occasional track day person who tries autocross for the first time never to see them again because they found it to difficult and decided to stick to track days? I'm all for change for good reasons, I'm just not convinced (yet) that this is one. My 2 cents

It should be obvious (my snarky comment clearly didn’t come across well) but we have an entire class (csm) dedicated to lower treadwear tires that people can run right now. Why can’t the track day crowds run in that class? What problem are we solving?

I agree with Porta: The "ST" in "CST" stands for "Street Tire" and we should stick to it (literally) being a "run what you brung" class ON street tires.

BUT if we do change the rules to a 100 treadwear minimum for CST, we keep it at that and go no lower...keep the R-comps and slicks in SM/CSM class where they belong thank ya.

As for the occasional track day guy who tries autocross for the first time: Why not stick them in CSM class like Marshall said? OR stick them in "NOV SM" class or "TO" if they feel intimidated OR just don't wanna run with the big dogs yet. If they really get hooked on AutoX and want to stay, they then could decide what class they want to compete in be it CST or CSM and with the appropriate treadwear tire that fits the rules.

I think more competitors have gravitated towards CST than CSM because of the open, less-restraining rules for car prep and the friendly-fun competitive atmosphere of the class along with the camaraderie amongst the drivers....plus we don't got enough monies for any R-compound purple crack

Looking 2018/2017 years of overall results say that no one has raced in CSM since 2016.

With CST already having very strong large turnout year after year, perhaps we can compromise by tweaking the rules for CSM to restrict tire wear ratings to DOT tires of 41tw and above?

That way, if it turns out that there is a decent population of drivers with only access to these DOT "track tires" that want to come and play, they might regularly return to future events with friends without fear that someone with a set of Hoosiers will show up and ruin their day.

This is the inevitable slippery slope that the whole moving "stock" back to "street tires".... The number the manufacturer molds on the side of the tire has very little to do with the durability or grip....

Jonathan Hartendorp wrote:I agree with Porta: The "ST" in "CST" stands for "Street Tire" and we should stick to it (literally) being a "run what you brung" class ON street tires.

BUT if we do change the rules to a 100 treadwear minimum for CST, we keep it at that and go no lower...keep the R-comps and slicks in SM/CSM class where they belong thank ya.

As for the occasional track day guy who tries autocross for the first time: Why not stick them in CSM class like Marshall said? OR stick them in "NOV SM" class or "TO" if they feel intimidated OR just don't wanna run with the big dogs yet. If they really get hooked on AutoX and want to stay, they then could decide what class they want to compete in be it CST or CSM and with the appropriate treadwear tire that fits the rules.

I think more competitors have gravitated towards CST than CSM because of the open, less-restraining rules for car prep and the friendly-fun competitive atmosphere of the class along with the camaraderie amongst the drivers....plus we don't got enough monies for any R-compound purple crack

Agreed, and I think there would be no harm in changing it to 100tw without much issue.

As long as R comp semi-slicks are not allowed we are all good. Those brings into play bigger issues than paying the premium for hoosiers (which I have no issue with), but needing things like trailers and tow vehicles, which is a whole different level of commitment. Personally I've been able to run semi slicks (for track days only) by removing the passenger seat and cramming wheels in the side/back of the car, but it's a pain and only something I do for track days, not something I want to do for AutoX, where driving to the track on the tires I'm running is so much easier. Something especially necessary in something like a lotus or porsche cayman with no cargo space.

Speaking from experience in terms of trying to sell my track day friends on AutoX, it isn't necessarily the classing that concerns them, but needing different tires to be competitive in a class that exists, not just in PAX (which is something they could care less about, and honestly something I find irrelevant as a CST driver.). One of my good friends runs track days in a cayman with R888Rs and NT01s. He has no desire to buy either hoosiers or Re71s just to join in class his car would fit in.

So if we gain even one regular driver and don't have any real cons to this proposal why not push it through?

Jonathan Hartendorp wrote:I think more competitors have gravitated towards CST than CSM because of the open, less-restraining rules for car prep and the friendly-fun competitive atmosphere of the class along with the camaraderie amongst the drivers....plus we don't got enough monies for any R-compound purple crack

Just my two cents, I've definitely given thought to joining CST after my Spyder's competitive life in ES expires (who knows when that'll be). I can't wait to put an engine swap in my car and make it into something I want, rather than sticking to a set of rigid SCCA rules.

That being said, I like how the 200TW tires are "settled" in terms of which ones are the top dogs. If it opens up to 100TW, wouldn't the top dogs in CST go into tire testing mode and buy a bunch of sub 200TW tires to test, thus driving up the cost of participation? If I was competing in CST aggressively, thats what I would do.

To take a page out of SCCA, why not create a CST 100TW and a CST 200TW? Everybody is happy, there are more classes, and more participation trophies for everyone

Jonathan Hartendorp wrote:I think more competitors have gravitated towards CST than CSM because of the open, less-restraining rules for car prep and the friendly-fun competitive atmosphere of the class along with the camaraderie amongst the drivers....plus we don't got enough monies for any R-compound purple crack

Just my two cents, I've definitely given thought to joining CST after my Spyder's competitive life in ES expires (who knows when that'll be). I can't wait to put an engine swap in my car and make it into something I want, rather than sticking to a set of rigid SCCA rules.

That being said, I like how the 200TW tires are "settled" in terms of which ones are the top dogs. If it opens up to 100TW, wouldn't the top dogs in CST go into tire testing mode and buy a bunch of sub 200TW tires to test, thus driving up the cost of participation? If I was competing in CST aggressively, thats what I would do.

To take a page out of SCCA, why not create a CST 100TW and a CST 200TW? Everybody is happy, there are more classes, and more participation trophies for everyone

The whole point of CST though is to be a true "catch-all". Splitting hairs regarding what street legal, non-slick, tire doesn't really seem to make sense. Why not provisionally approve this and if we see a massive change in the results we can re-evaluate it? Unless we want to go all GRM and bring out a crop of 200tw's and 100tw's and do back to back testing we won't know if they have the potential to change the current status quo.

2 cents, with no dog in this fight...Lowering treadwear ratings to a number outside of common rulesets opens up a future potential difficulty of someone actually coming up with a good tire at the 100TW mark, and suddenly the class is upset until a rule revision can take place, banning anyone who bought in on what was a legal option, or upsetting everyone who was sticking with competitive 200TW tires.

It's not out of the realm of possibility that a new hoosier looks at the numbers and says "Hey, this could be 100TW.." and stamps it on the chassis.

It also sounds like there's already a class where lower treadwear tires are permitted to begin with?

Staying aligned with SCCA/CAM/Good Guys/Optima/Chump/Lemons/GridLife who all currently require 200TW at some level of their classing seems more inviting to people who have complied with those rules, as people who have opted to get sub 200TW have already accepted their classing in these other series.

If, if, if the Toyo intermediate (pick one model) is proven slower than say the RE-71R, you could say all 140 or 200tw (what it is now) and Toyo XYZ intermediate can run. The point is. "Don't just allow all 100tw." This would help people with 13 and 14 inch wheels that can't find tires and the few track day drivers with 16s.... By only allowing approved listed intermediate 100tw tries to run we can pull them if the tire changes to a soft slick at some point. I think allowing all 100tw in any configuration is too open.

I have information from what I believe is a very good source that one of the top R compound manufacturers actually is considering a slightly longer lived "R compound".

My guess is that you do NOT want that tire - or even the current A7, as Anthony points out - legal in CST. That's why we have "Run What Ya Brung" classes for both true street tires and competition tires.

I'm with Marshall: I don't understand how this helps attract participants. If we have even a small group of people that want to run on 100 treadwear competition tires, all they have to do is run in CSM. Yeah, someone could throw on an A7 and screw them, but that's exactly what they're theoretically proposing to do to those CST participants who are actually running on 200 TW or the now-rare 180 TW tires.

When we discussed this on our last region call, I thought I'd wait for the polling of the CST participants. That seems to have happened in this thread, with Michael Bradley making good points. If you want RA1s, or anything else sub-140, why not run in CSM?

Are we trying to attract new participants? Driving cars that do not readily fit the rules we compete by opens an opportunity to increase our numbers when we allow people to drive what they already have.

Might the line between CST and CSM need to be redrawn as 100 and above, or 99 or less.

I have a 1987 BMW 325 with a '91 motor. Running in XP was never anything I wanted to pursue, those that know me might understand that Hoosiers are not what I would spend the money on. I have driven the car on Toyo RA-1's, Bridgestone RE-71's and I have a set of BFG's Rival S next in the rotation. The events have included local auto cross's(BMWCCA and SCCA) and Lone Pine. What I have learned to date, long lasting track tires are not great auto cross tires. Next, even almost warn out decent autocross tires are faster but have a much shorter life span when driven on at a track event. But, these are lessons that result from seat time.

Per Bob's proposal,"This would allow people that are doing track days with..." to get involved. The chance that they are going to run enough events to chase a jacket, not likely.

David Barrish wrote:Per Bob's proposal,"This would allow people that are doing track days with..." to get involved. The chance that they are going to run enough events to chase a jacket, not likely.

So if they aren't worried about competing for a jacket, why not just run CSM? If they like what we do and want to get serious, they can then comply to whatever class rules they want to compete in if it isn't CSM. Just like everyone else that competes.

Since light is faster than sound...many people look bright until they speak...